Tool for a vacuum cleaner

ABSTRACT

A vacuum cleaner flexible duct. The flexible duct includes a helical frame and a helical strip. The helical frame is formed of a rigid material and includes a plurality of loops spaced about a helical axis. The helical strip is formed of pliable material and is provided between the loops of the helical frame to seal the frame. Each loop of the frame includes a central band with at least one wing. The helical strip is secured to the at least one wing such that the exterior surface of the helical strip is flush with the exterior surface of the central band.

REFERENCE TO RELATED APPLICATIONS

This application claims the priority of United Kingdom Application No.1612135.2, filed Jul. 13, 2016, the entire contents of which areincorporated herein by reference.

FIELD OF THE INVENTION

The present invention relates to a flexible duct for a vacuum cleaner.More specifically, the present invention relates to a flexible duct fora vacuum cleaner tool.

BACKGROUND OF THE INVENTION

FIGS. 1 and 2 are examples of flexible crevice tools 100, 200 that canbe used with a vacuum cleaner. The tools 100, 200 are intended to reachinto and clean crevices or gaps to be cleaned. Both of the tools shownin FIGS. 1 and 2 comprise a flexible duct 300 formed from a pliablecasing material 400 which is reinforced by a rigid frame 500. Anysteering force applied to the tool 100, 200 when it is in a crevicecauses the pliable casing material 400 to bend. The rigid frame 500 isused to improve the control and steering of the tool, and to prevent theflexible duct 300 from folding over itself or kinking. Folding orkinking of the duct should be prevented as this can restrict the flow offluid drawn through the tool 100, 200, and may also cause damage to theflexible duct 300.

The tools 100, 200 shown in FIGS. 1 and 2 have rigid frames 500 with apliable casing material 400 fitted over the top to seal the duct. Arelatively thick casing material 400 is required in order to make aresilient duct 300. Thus, the casing material 400 stands proud of theframe. The pliable casing 400 placed over the top of the frame 500 cantherefore increase the overall profile of the tool. Although a moreflexible tool can been created by using a frame 500 and casing 400, theadded thickness of the pliable casing material 400 may prevent the toolfrom used in narrower crevices.

SUMMARY OF THE INVENTION

In a first aspect, the present invention provides a vacuum cleaner toolcomprising a flexible duct, the flexible duct comprising a helical framebeing formed of a rigid material and comprising a plurality of loopsspaced about a helical axis, and a helical strip being formed of pliablematerial and provided between the loops of the helical frame to seal theframe, wherein each loop comprises a central band with at least onewing, the helical strip is secured to the at least one wing such thatthe exterior surface of the helical strip is flush with the exteriorsurface of the central band.

The pliable sheaths that are used in the prior art examples are placedover the tool to conceal the frame. In contrast to these sheaths, theduct of the present invention requires a helical strip to seal the spacebetween the rigid frame loops. The helical strip may be in the form of asingle ribbon, or a series of bands that together provide a sealed duct.In other words, the helical strip is used to link the loops of thehelical frame. The helical strip may be overmoulded or bonded onto thehelical frame. Less material can then be used to make a sealed duct byproviding a helical strip only between the loops of the helical frame,compared to a full sheath covering both the loops and the space betweenthe loops. In addition, the helical strip between the loops of thehelical frame can be formed so that it is flush with the profile of theloops, instead of fitting a sheath over the frame and increasing theprofile of the tool. Thus, the profile of the tool can be reduced sothat it can fit into narrower gaps and crevices. Although at least partof the helical frame may remain uncovered to the user (i.e. the centralband), the helical strip can be used to cover parts of the loops. Forinstance, the at least one wing on the loops can be covered or concealedby the helical strip whilst the central band of the loops are uncoveredor exposed.

The at least one wing may extend all the way around the central band ina direction parallel with the helical axis, and the height of the atleast one wing may be less than the height of the central band in adirection normal to the helical axis. A greater contact area with thehelical strip can be achieved by having a wing that has the same shapeas, and extends away from, the edge of the central band. In addition,the strength of the at least one wing is increased if it extends aroundthe central band of each loop. For at least these two reasons, it can besaid that the robustness of the duct is improved such that damage to theduct or tool can be prevented. The cross-sectional profile of each loophas a raised section, which is the central band, and lower section,which is the at least one wing. Thus, it can be said that the height ofthe at least one wing may be less than the height of the central band ina direction normal to the helical axis. The central band may be flankedby a wing on each side, so that the general profile of each loop can besaid to have a raised central section (i.e. the central band) flanked bytwo lower sections (i.e. the wings). Both the inner and outer surfacesof the helical strip are provided flush with each of the central bandonce the strip is secured to the frame.

The at least one wing may have at least one anchor for securing thehelical strip to the frame. The at least one anchor point may be a hole,or a keying feature that engages with the helical strip allowing for amore robust tool. The helical strip is provided only in the spacebetween the loops of the frame. Thus, the anchor points allow the toolto withstand flexing without the helical strip coming away orunravelling from the frame. This is to be avoided as the helical stripprovides a means for sealing the duct.

The cross section of the flexible duct may be a general rectangularshape, comprising two longer side surfaces connected by shorter top andbottom surfaces. The general rectangular shape of the flexible ductallows for a narrow profile crevice tool that can fit into most gaps andcrevices. The requirement of a general rectangular shape does notpreclude the curving or shaping of the sides of the rectangular duct foraesthetic or ergonomic purposes.

The helical strip may have indents provided on a surface of the flexibleduct. The indents allow for improved flexibility of the duct and alsoprovide a crease for the duct to fold into as it flexes. The indents maybe provided on a side surface of the flexible duct. This allows forimproved flexing of the duct in the desired side to side (or left/right)direction, instead of flexing in an up/down direction.

The tool of the present invention may be a telescopic tool comprising afirst and second conduit; the first conduit has a narrower profile thanthe second conduit, the second conduit surrounds the first conduit suchthat the first conduit slides in and out of the second conduit allowingfor extension of the tool, and the flexible duct forms part of the firstconduit. The use of the flexible duct on a telescopic tool allows for alonger tool that can be placed into gaps or crevices to be cleaned.Furthermore, the provision of a rigid conduit together with a conduithaving the flexible duct improves the handling and manoeuvrability ofthe tool since the user can hold onto the rigid conduit and steer to thetool.

In a second aspect, the present invention provides a vacuum cleaner ductcomprising, a helical frame being formed of a rigid material andcomprising a plurality of loops spaced about a helical axis, and ahelical strip being formed of pliable material and provided between theloops of the helical frame to seal the frame, wherein each loopcomprises a central band with at least one wing, the helical strip issecured to the at least one wing such that the exterior surface of thehelical strip is flush with the exterior surface of the central band.

BRIEF DESCRIPTION OF THE DRAWINGS

In order that the present invention may be more readily understood, anembodiment of the invention will now be described, by way of example,with reference to the accompanying drawings, in which:

FIG. 1 is a tool forming part of the prior art;

FIG. 2 is another tool forming part of the prior art;

FIG. 3 is a perspective view of a tool comprising a flexible duct of thepresent invention;

FIG. 4 is a perspective view of the flexible duct of the presentinvention;

FIG. 5 is an exploded view of the flexible duct of the presentinvention, with an insert showing the details of the frame;

FIG. 6 is a top view of the tool of FIG. 3; and

FIG. 7 is a plan view of the tool of FIG. 3.

DETAILED DESCRIPTION OF THE INVENTION

FIG. 3 shows a tool 1 comprising a first conduit 2, a second conduit 3,a first connector 4 and a second connector 5. The first conduit 2 has anarrower profile than the second conduit 3, and the second conduit 3surrounds the first conduit 2 such that the first conduit 2 slides inand out of the second conduit 3, allowing for extension of the tool 1.When the tool 1 is extended, the first conduit 2 is revealed from thesecond conduit 3. Such a tool 1 can be said to be telescopic.

The first conduit 2 is connected at one end to the second conduit 3 andat the opposite end to the first connector 4. The second conduit 3 isconnected to the second connector 5. The second connecter 5 is locatedat the end opposite to where the first conduit 2 connects to the secondconduit 3. The first connector 4 can be used for connecting a nozzle orcleaner head to the end of the tool 1. Alternatively, the firstconnector 4 can act as an inlet for the tool without the need for anozzle or cleaner head attachment. The second connector 5 is used toconnect the tool 1 to a wand or hose that further connects to a vacuumcleaner.

The tool 1 further comprises locking means 6 for locking the conduits2,3 of the tool 1 out at maximum extension (as shown in FIG. 3) and alsofor locking the first conduit 2 in a retracted position when it islocated within the second conduit 3.

The first conduit 2 comprises a flexible portion or duct 7 and rigidportions 8 at either end of the flexible duct 7. The flexible duct 7 isshown in more detail in FIGS. 4 to 7 and comprises a helical frame 9 anda helical strip 10. The flexible duct 7 has a generally rectangularshape cross section, with two longer side surfaces 11, 12 (best shown inFIG. 6) and two shorter top and bottom surfaces 13, 14 (best shown inFIG. 7). The flexible duct 7 can flex in directions normal to thehelical axis 15. For example, the flexible duct 7 is free to flex in aleft to right direction, and also in an up and down direction, as shownin FIGS. 6 and 7 respectively. Dashed lines are used to illustrate thegeneral degree of movement of the flexible duct 7 in directions normalto the helical axis 15.

The helical frame 9 is formed of a single piece of rigid material andcomprises a plurality of loops 16 that are arranged around the helicalaxis 15. The loops 16 are spaced at regular intervals along the helicalaxis 15 with a space between each loop 16. The profile of each loop 16is shown in more detail in FIG. 5. Each loop 16 comprises a central band17 flanked by wings 18, 19 on either side of the band 17, the band 17being of greater thickness than the wings 18, 19. That is to say thatthe height of the wings 18, 19 is less than the height of the centralband 17 in a direction normal to the helical axis 15. Each wing 18, 19extends all the way around the central band 17 in a direction parallelwith the helical axis 15 and is provided with anchors 20 which are usedas keying features during the manufacturing process of the tool 1. Onewing 19 is provided with two projections 21 that extend towards anadjacent loop 16. The projections 21 extend in a direction that isparallel to the helical axis 15. The projections 21 are positioned onthe top and bottom of the wing 19 (best shown in FIG. 5). Theprojections 21 act to restrict the movement of the flexible portion 7 inthe up and down direction relative to the movement of the flexibleportion 7 in the left to right direction.

The helical strip 10 is formed of a single piece of a pliable materialin the form of a tape, bandage or ribbon. The helical strip 10 isextends along the helical axis 15 and around part of the helical frame9. Specifically, the helical strip 10 is either overmoulded onto orbonded to the helical frame 9 such that the strip 10 fills the spacebetween each of the loops 16, providing a continuous coupling betweenthe loops 16 of the frame. The helical strip 10 seals the spaces in thehelical frame 9 to provide a duct for fluid to be drawn through.Furthermore, the helical strip 10 is provided between the loops 16 onlyon the wings 18, 19, such that the exterior of the helical strip 10 isflush with the exterior of the central band 17. As shown in FIG. 4, thecentral band 17 of each loop 16 is exposed along the length of the duct7. Since the helical strip 10 is provided in the space between the loops16 and flush with the loops 16 the overall exterior profile of theflexible duct 7 is reduced.

The helical strip 10 is able to flex and stretch, allowing the flexibleportion 7 to bend or twist from a straight position and return back toits original shape. The helical strip 10 has indents 22 provided on theside surfaces 11, 12 of the duct 7. The indents 22 improve theflexibility of the duct 7 in two ways. Firstly, the indents 22 reducethe stiffness of the helical strip 10 on a side surface 11, 12 thatlengthens during a flexing movement (that is to say, the side surface11, 12 on the outside of the bend of the flexible duct portion 7).Secondly, the indents 22 allow for the material of the helical strip 10to crease and fold more readily on a side surface 11, 12 that contractsduring a flexing movement (that is to say, on the side surface 11, 12 onthe inside of the bend of the flexible duct portion 7).

The anchors 20 provided on the wings 18, 19 of each loop 16 of the frame9 act as keying features as the strip 10 is overmoulded onto the frame9. During manufacture, the pliable material flows over the wings 18, 19and into or onto the anchors 20. The anchors 20 are holes that areshaped so that the helical strip 10 is secured onto the frame 9 once thepliable material has cured. The pliable material is only provided on thewings 18,19 such that, once cured, the exterior surface of the helicalstrip 10 is flush with the exterior of the central band 17. In addition,a mould insert can be placed inside the flexible portion 7 of the firstconduit 2 and against the inside surface of the loops 16 such that thepliable material flows and cures against the mould insert. The mouldinsert is then removed after curing to leave behind a smooth interiorsurface of the duct 7 as the helical strip 10 is cured flush with theinterior profile of the loops 16.

During use, the tool 1 is extended so that the first conduit 2 isexposed as it slides outs of the second conduit 3. The travel of thefirst conduit 2 is locked when the tool 1 is in an extended position (asshown in FIG. 3). The profile of the tool 1 is such that at least thefirst conduit 2 can be placed into a gap or crevice. The user canmanoeuvre the tool 1 by holding either the second conduit 3, or byholding an extension wand or handle connected via the second connector5.

As the tool 1 is manoeuvred into a crevice, the flexible duct 7 of thefirst conduit 2 can bend or flex against the walls or floor of thecrevice. The user will naturally force the tool 1 against thesurface/floor of the crevice to be cleaned. As the force is applied, theflexible duct 7 will flex in an up/down and/or left/right direction. Asthe duct 7 bends or flexes in the up down direction, the projections 21limit the range of movement of the helical frame 9. This improves thecontrol of the tool 1 and gives the user the ability to steer the tool 1in a crevice without the duct 7 flexing in an unwanted direction (i.e.up/down direction). In addition, prevents the flexing of the duct 7beyond a point where damage or kinking would occur. Thus, although themaximum range in movement in the up and down direction is decreased, theduct 7 is protected against folding or kinking, and also reinforced toprevent any damage to the tool 1.

The movement of the flexible duct 7 in the left and right direction isimproved by the indents 21 that are provided on the side surfaces of thehelical strip 10. In use, the indents 21 provide improved flexibility,in that they are able to stretch more easily than the rest of thehelical strip 10 since less material is present. In addition, theindents 21 provide a crease or fold for the helical strip 10 to bendinto when flexing the duct 7. Thus, the steering of the tool 1 in aleft/right direction is easier relative to steering in an up/downdirection.

Although the flexible duct 7 is shown as part of a tool 1 for a vacuumcleaner, it will be appreciated that such a duct could be used on otherparts of the vacuum cleaner, such as a suitable replacement for a hose,or a tube, or a conduit connecting parts of a vacuum cleaner.

1. A vacuum cleaner tool comprising a flexible duct, the flexible ductcomprising: a helical frame being formed of a rigid material andcomprising a plurality of loops spaced about a helical axis; and ahelical strip being formed of pliable material and provided between theloops of the helical frame to seal the frame; wherein each loopcomprises a central band with at least one wing, and the helical stripis secured to the at least one wing such that an exterior surface of thehelical strip is flush with an exterior surface of the central band. 2.The vacuum cleaner tool of claim 1, wherein the at least one wingextends all the way around the central band in a direction parallel withthe helical axis, and a height of the at least one wing is less than aheight of the central band in a direction normal to the helical axis. 3.The vacuum cleaner tool of claim 1, wherein the at least one wing has atleast one anchor for securing the helical strip to the frame.
 4. Thevacuum cleaner tool of claim 1, wherein a cross section of the flexibleduct is a rectangular shape, comprising two longer side surfacesconnected by shorter top and bottom surfaces.
 5. The vacuum cleaner toolof claim 4, wherein the helical strip has indents provided on a surfaceof the flexible duct.
 6. The vacuum cleaner tool of claim 5, wherein theindents are provided on a side surface of the flexible duct.
 7. Thevacuum cleaner tool of claim 1, wherein the tool is a telescopic toolcomprising a first conduit and a second conduit; and wherein the firstconduit has a narrower profile than the second conduit, the secondconduit surrounds the first conduit such that the first conduit slidesin and out of the second conduit, allowing for extension of the tool,and the flexible duct forms part of the first conduit.
 8. A vacuumcleaner duct comprising: a helical frame being formed of a rigidmaterial and comprising a plurality of loops spaced about a helicalaxis; and a helical strip being formed of pliable material and providedbetween the loops of the helical frame to seal the frame; wherein eachloop comprises a central band with at least one wing, and the helicalstrip is secured to the at least one wing such that an exterior surfaceof the helical strip is flush with an exterior surface of the centralband.
 9. The vacuum cleaner duct of claim 8, wherein the at least onewing extends all the way around the central band in a direction parallelwith the helical axis, and a height of the at least one wing is lessthan a height of the central band in a direction normal to the helicalaxis.
 10. The vacuum cleaner duct of claim 8, wherein the at least onewing has at least one anchor for securing the helical strip to theframe.
 11. The vacuum cleaner duct of claim 8, wherein a cross sectionof the flexible duct is a rectangular shape, comprising two longer sidesurfaces connected by shorter top and bottom surfaces.
 12. The vacuumcleaner duct of claim 11, wherein the helical strip has indents providedon a surface of the duct.
 13. The vacuum cleaner duct of claim 12,wherein the indents are provided on a side surface of the duct.